I sprained my knee last summer and i think i might have just sprained it again. what can i do to help it heal faster?

Ice,rest and a brace: If it is recent sprain you can put ice, use cruthes and rest your knee and immobilise with a knee brace, if does not get better you need to see your doc and have MRI done to rule out internal injuries like torn meniscus or ligament.

Rest: Definitely rest your knee. You may have an injury that is flaring up from the initial damage last summer. You may consider having an MRI to r/o any tears or injury that will require surgery to repair.